Many commercial, industrial, and even residential establishments have cold rooms or refrigerated rooms primarily for storage and preservation of food items, as in restaurants, grocery stores, hotels, taverns, hospitals, food processing establishments and the like. The energy requirements of operating such a cold area can be significant. In winter, particularly in northern climates, this results in the anomally that energy is being expended to cool a room in a building that is being heated. In northern climates, during much of the year, the ambient outside temperature of the air is at or below the temperature at which a cold room is normally maintained. Generally the temperature maintained in such cold rooms is above freezing. Storage of food items of the type normally stored in cold rooms directly in an outside environment results in freezing or in alternately freezing and thawing.